Abstract: An image processing apparatus includes an obtaining unit and a combining unit. The obtaining unit obtains, from attribute information, data format information indicating data formats of first image data representing a first image and second image data representing a second image. The attribute information is included in the first image data and the second image data. The first image is printed at predetermined positions in all units of printing. The second image is changed in accordance with the individual units of printing and is printed at predetermined positions in the individual units of printing. The combining unit divides the first image data and the second image data in accordance with the data formats, and combines compressed data generated by compressing raster data of the first image data with compressed data generated by compressing raster data of the second image data, depending on amounts of image represented by divided portions.

Abstract: An image forming apparatus that performs correction to make gradation values adding both of two head areas (A+C, B+D) approximately equal. An area whose density is the lowest is set as a target density. Assuming densities for head areas A=70, B=100, C=40, D=90, head areas B and D are corrected with correction amount that ?B become equal to ?D (?B=?D=40) in accordance with target value (A+C=100).

Abstract: An image processing method includes: forming a density unevenness measurement test image based on image data subjected to unevenness correction processing to correct density unevenness, using a preset unevenness correction value; acquiring a pre-conversion density measurement value that is a density measurement value of each density setting value for every recording element in the density unevenness measurement test image before processing after image formation using a recording head; converting the pre-conversion density measurement value into a post-conversion density measurement value corresponding to a density measurement value after the processing, using a density measurement value conversion value derived beforehand and indicating a conversion relationship of density measurement values before and after the processing for every density setting value and to which the set unevenness correction value is applied as the density setting value; and deriving a new unevenness correction value using the post-conve

Abstract: In a multi-layer printer, the base white layer that is applied during printing is modified using the image to be printed. By altering the white layer to reflect the density of the top image, it is easier to reach saturation (density/gamut) without adding large amounts of ink. Thus, such undesirable side effects, such as gloss-banding are avoided.

Abstract: Provided are an image processing apparatus and an image processing method capable of reducing color unevenness due to variations in ejection characteristics among a plurality of nozzles when printing an image using a plurality of inks. To that end, a first image which is made up a color with noticeable color unevenness and similar colors is printed onto a print medium. The user then specifies a color and a nozzle position where color unevenness has occurred. On the basis of these results, parameters are set for a correction table referenced by an MCS processor. In so doing, it becomes possible to address the factor causing the color unevenness, and mitigate the effects of color unevenness in a focused way without incurring increases in processor load, memory requirements, or processing time as compared to the case of calibrating all lattice points.

Abstract: A printing apparatus in which printing is performed using an ink jet method includes a first ink jet head that discharges ink droplets of ink of a first color which is a color of the same color type as an expression color that is set in advance, a second ink jet head that discharges ink droplets of ink of a second color which is a color of the same color type as the expression color and is different from the first color, and a control unit which makes the first and the second ink jet head perform printing with the expression color on a medium by setting a ratio of a discharge amount of ink of the first color by the first ink jet head to a discharge amount of ink of the second color by the second ink jet head to a discharge rate which is calculated in advance.

Abstract: A defective recording element detecting apparatus includes: a read image data acquiring device which acquires read image data of a test pattern recorded on a recording medium by a recording head having recording elements; a reference area setting device which sets a reference area including a part of the test pattern on a read image representing image contents of the read image data; a comparison area setting device which sets a comparison area on the read image; a correlation operation device which performs a correlation operation between the comparison area and the reference area; a distortion correction value determining device which determines a distortion correction value, from a result of the correlation operation; an image distortion correcting device which corrects image distortion of the read image using the distortion correction value; and a defective recording element determining device which identifies a defective recording element according to the corrected read image.

Abstract: A specific gamut of colors extending a reproduction range of colors in a color space is set to make for any ink color belonging to the specific gamut a conversion from CMYK dot pattern data into numbers of ink drops to be discharged from an inkjet head, using as a lookup table an extended pattern table having a maximal drop number ‘7’. For ink colors belonging to a gamut of colors outside the specific gamut, a default pattern table having a maximal drop number ‘5’ is used as a lookup table for the conversion from CMYK dot pattern data into ink drop numbers.

Abstract: The use amount of clear ink is set to minimize the hue difference ??s?d from each of the colors corresponding to input signal values. The use amount of the clear ink to provide the minimum hue difference ??s?d is varied depending on the use amount of color ink used for the color corresponding to the input signal value. A color conversion table having output values of the use amount and ink color data corresponding to the use amount is set. The color conversion in such a relationship is performed, whereby the bronzing color is recognized as a color close to the print color. As a result, undesired bronzing is lessened, so that degradation in image quality can be suppressed.

Abstract: Uneven glossiness is effectively suppressed between areas where light inks are mainly used and areas where dark inks are mainly used. The gloss is raised in areas where dark cyan ink C is used. In other words, the application amount of second clear ink applied by after application printing is set to 32% at primary cyan (grid point 16) to equalize the gloss with areas where light cyan ink LC is used. Also, the application amount of first clear ink applied by common printing is set to 32% in a highlight portion (grid point 8) to equalize the gloss with the maximum gloss reached using dark cyan ink C. In so doing, it is possible to keep the gloss nearly constant over the entire range from white to cyan, or in other words, suppress uneven glossiness.

Abstract: A printer is disclosed in one example. The printer controls the amounts of the inks that are used when printing. The printer prints colors near saturation onto a media using mostly a first ink and prints saturated colors onto the media using mostly a second ink. The second ink has a reduced loading of the colorant in the first ink.

Abstract: An image forming apparatus includes a sheet feed conveying unit having an outlet for a recording medium on one side; at least one image forming unit having an inlet for the recording medium on one side and an outlet for the recording medium on the other side; and a sheet eject conveying unit having an inlet for the recording medium on one side, wherein the sheet feed conveying unit, the image forming unit, and the sheet eject conveying unit are arranged along a conveying direction of the recording medium; the outlet of the sheet feed conveying unit matches the inlet of the image forming unit; the outlet of the image forming unit matches the inlet of the sheet eject conveying unit; and the sheet feed conveying unit, the image forming unit, and the sheet eject conveying unit are connected to each other in a separable manner.

Abstract: Desired designated sections are selectively extracted from a color image to be printed, the extracted designated sections are converted into a solid black image having a high thermal energy absorbency, and the solid black image is printed on the foaming layer surface of a supplied thermal expansion sheet. Next, thermal energy is applied by a halogen lamp in a thermal expansion processing unit, causing the solid black image section to expand and rise. Furthermore, in an ink jet printer unit, a prescribed color that is a background color is printed on the entire foaming layer surface of the thermal expansion sheet including the raised sections. Furthermore, the color image to be printed is printed thereon by an ink jet recording method to obtain color image three-dimensional printed material.

Abstract: A printer includes an ink reservoir that includes yellow ink, cyan ink, and magenta ink. The printer includes an ink dispenser that employs a yellow distribution setting to increase the drop volume of yellow ink droplets and lower the drop frequency of the yellow ink droplets on the media with respect to the cyan ink droplets and/or magenta ink droplets to control the lightfastness of the print on the media.

Abstract: Printing methods are provided. In one method, printing an inkjet image using a liquid hydrophilic inkjet ink onto a surface of a semi-absorbent recording medium generating a toner image having toner particles arranged conforming to the inkjet image and transferring the toner image onto the recording medium where an unabsorbed volume of the inkjet ink is present on the recording medium. The toner particles manage unabsorbed volumes of the inkjet ink to protect the recording medium from image artifacts that can be created by an unabsorbed volume of the inkjet ink on the surface without a liquid management toner image.

Abstract: A printing device using a print head ejecting ink from a plurality of nozzles to print ink dots of a plurality of dot diameters, includes a print-characteristic acquisition unit obtaining print characteristic information on dot diameters of ink dots to be printed per each predetermined portion of the plurality of nozzles, a distribution ratio determination unit determining a distribution ratio for distributing image data to the predetermined portions of the plurality of nozzles based on the information, a dot print position determination unit quantizing the image data to determine a dot print position based on the image data and sizes and an array of thresholds; and a plurality of masks based on dot distribution order determined according to the distribution ratio, distributing printing of each of the ink dots of the plurality of dot diameters to the dot print position determined by the dot print position determination unit.

Abstract: In a recording apparatus, a dot diameter of a first color ink formed by discharging a predetermined amount of the first color ink onto a surface of a second color ink fixed on a recording medium is smaller than a dot diameter of the second color ink formed by discharging the predetermined amount of the second color ink onto a surface of the first color ink fixed on the recording medium, and a recording head discharges the plurality of inks such that with respect to pixels forming an image in a unit area, pixels formed by discharging the second color ink and the first color ink in this order are greater than pixels formed by discharging the first color ink and the second color ink in this order.

Abstract: Displacement information indicating a displacement amount of landing position in a main scanning direction of ink droplets discharged respectively from the nozzle of the head module of the same array of the line head of each color is acquired for each head module of the same array (steps S5, S7). Based on the displacement information and concentration information for each array, a color degree of an image when the discharge amount of ink droplets discharged from a nozzle of a head module of each color is not adjusted is specified for each head module of each array (step S9). A correction voltage value of a drive signal for the discharge of the nozzle of the head module of each color, which is suitable to return the specified color degree to “0”, is calculated (step S11) and each corresponding nozzle is driven by the drive signal of the correction voltage value.

Abstract: Curing processing is realized according to differences in absorption characteristics of activation light among inks and characteristics of layers to be formed with the inks. A scanning device reciprocally moves in a first direction an inkjet head including a first nozzle array ejecting a first ink and a second nozzle array ejecting a second ink; a relative movement device relatively moves a recording medium in a second direction with respect to the head; an ejection control device divides the nozzle array into regions in the second direction and controls ink ejection for each unit of the divided nozzle region; an activation light irradiation device irradiates the inks deposited on the medium with the activation light; an irradiation region dividing device divides an irradiation range into divided irradiation regions corresponding respectively to the divided nozzle regions; and a light quantity control device controls light quantities respectively for the divided irradiation regions.

Abstract: A printing apparatus includes (A) a head that discharges first ink and second ink having a color different from that of the first ink, (B) an optical sensor that includes a light source and a light receiving section, and (C) a controller. In the printing apparatus, when the controller corrects a discharge amount of the second ink, the controller causes the head to discharge the first ink to form a first pattern on a medium, causes the optical sensor to detect light reflected from the first pattern, causes the head to discharge the second ink to form a plurality of second patterns having different gradation values on the first pattern, and causes the optical sensor to detect light reflected from the second pattern.

Abstract: A calculator calculates a total value of tone values of all pixels in each aggregation by allocating each pixel of M-valued image data to one aggregation. Each block is either one of ejection-port groups including ejection ports having a common liquid channel serving as a liquid supply source or one of divided ejection-port groups. Each aggregation includes pixels of the M-valued image data corresponding to dots formed on a medium when liquid is ejected from ejection ports in one block during one L ejection period. Each L ejection period is obtained by dividing, by a plural number, a number of ejection cycles required to record an image on one recording medium. A tone-value reducer reduces tone values of at least part of pixels in an adjustment-requiring aggregation so that the total value becomes less than a threshold. A transmitter transmits the adjusted M-valued image data to a liquid ejecting device.

Abstract: A corrector performs designating a target pixel belonging to a pixel array corresponding to an ejection port, the target pixel being designated sequentially as one of pixels arranged in an array direction, the pixel array being formed with the pixels in the N-value image data corresponding to dots formed by the ejection port respectively, allocating a corresponding one of N representative tone values out of L tone values of L tones to a tone value of the target pixel of the N-value image data, adding the correction value to a representative tone value of the target pixel, thereby obtaining a corrected tone value of the target pixel, quantizing the corrected tone value of the target pixel to N tones; and diffusing an error generated in quantizing the corrected tone value to the corrected tone value of an adjacent pixel adjacent to the target pixel in the array direction.

Abstract: A control section is included which performs a background image pre-printing which enables each ink to be ejected from the upstream side background color nozzle row and the downstream side color nozzle row and can land the color ink after landing the background color ink on the medium in a region concerning the transport direction, and a background image post-printing which enables each ink to be ejected from the upstream side color nozzle row and the downstream side background color nozzle row and can land the background color ink after landing the color ink on the medium in a region concerning the transport direction, the control section performing the printing so as to switch over the background image pre-printing and the background image post-printing on one medium.

Abstract: A density correction system includes a conveyance unit that conveys a recording medium, a first ink ejection unit that ejects ink in a multi-drop driving system to the recording medium based on image data, a second ink ejection unit that ejects ink in the multi-drop driving system to the recording medium based on the image data and in which a volume per one drop is smaller than that of the first ink ejection unit, and a control unit that corrects number of drops from the first ink ejection unit and number of drops from the second ink ejection unit, which constitute a droplet amount for one pixel on the recording medium subjected to image formation.

Abstract: There is provided a printing apparatus which is configured to control a basic color in performing the basic color in a printing medium. The printing apparatus includes: a table in which a correspondence relationship between a grayscale value in image data of the basic color and a color material amount is defined; an obtaining section which is configured to obtain a density range of a color which is to be printed on the basis of the image data of the basic color; and an adjustment section which is configured to adjust a grayscale range of the table so that the grayscale value corresponding to a color material amount range which corresponds to the density range of the color is increased.

Abstract: An image forming apparatus is disclosed which reads a test pattern, including a reading unit, a relative movement unit, a second detected data obtaining unit which obtains one or more second detected data sets of a reflected light which is received from a scanning position of a light by a light receiving unit while the reading unit moves relatively with respect to the recording medium before the test pattern is formed, a first detected data obtaining unit which obtains one or more first detected data sets of the reflected light which is received by the light receiving unit when the light moves over the test pattern at generally the same scanning position as the scanning position while the reading unit moves relatively with respect to the recording medium after the test pattern is formed, and a signal correction unit.

Abstract: A method of increasing a dynamic range of grey-scale printing by a first print head of a drop on demand inkjet printer, the first print head having a droplet orifice, the method comprising in addition to selectively supplying no signal for not ejecting a drop of ink, or a first signal for ejecting a first droplet size, further comprises optionally supplying a second signal for ejecting a second droplet size.

Abstract: An image may be printed at variable speed. An image density profile provides an estimation of power to be consumed while printing the image. A power consumption profile is generated based on the image density profile and by taking into account distance offsets between nozzles that are used to print the image. The image may be printed at different speeds based on the power consumption profile.

Abstract: A rim is provided for a bicycle wheel having an axis about which the wheel rotates and a center plane normal to the axis, including a tire-engaging portion located at an outer perimeter of the rim. An inner perimeter portion is located radially inwardly from the tire-engaging portion. The rim includes a first sidewall and a second sidewall spaced from the first sidewall. The first and second sidewalls extend between the tire-engaging and inner perimeter portions. An image receiving area is located on each of the first and second sidewalls and a non-contact printed graphic is disposed on at least some of the image receiving area.

Abstract: The present invention has an objective of providing an image formation apparatus that can output binary image data on a printing medium with a favorable quality. According to the present invention, a plurality of different pieces of mask data stored in a storage unit is used to generate a plurality of different pieces of divided data. Then, the frequency characteristic information of the respective plurality of generated thinned images is calculated. Thereafter, the pieces of frequency characteristic information of the respective plurality of generated thinned images are compared to select, from among the plurality of pieces of mask data stored in the storage unit, a divided mask pattern to be used for the input image data. Then, the selected divided mask pattern is used to form the image.

Abstract: The invention relates to a printing method of creating an image on a medium by discharging a plurality of colored inks each containing a colorant and clear ink containing no colorant from a nozzle toward the medium. Further the colored inks are discharged from the nozzle toward a unit region defined in the medium by an amount determined on the basis of respective amounts of cyan ink and magenta ink included in the colored inks to be discharged to the unit region.

Abstract: A head unit is provided that includes a plurality of head groups having a first head and a second head in a direction which crosses a transport direction of a medium. Color difference is obtained which indicates difference in color between patches formed for each band using dots having the same dot diameter from among a plurality of patches based on the result of color measurement performed on a test pattern which includes the plurality of patches for each band, the plurality of patches being formed for each head group using dots having different dot diameters. The amount of first ink and the amount of second ink, which are respectively ejected from the first head and the second head which are included in all the head groups, are adjusted such that the dot diameter becomes the dot diameter which is determined based on the color difference.

Abstract: A method produces a printing image formed of sections on a material using two inkjet printing heads. The printing image has first and second printing image sections meeting at a y coordinate Y1. The method includes choosing a data stripe extending in the x direction having a width about the location Y1, and examining the data in the selected stripe for a data field of the extent dx in the x direction and dy in the y direction, in which edge detection is possible. The data field is selected and the x coordinate x1 and the y coordinate y1 of the data field are captured. The printing image is then produced. An image of a measurement field correlated to the data field is recorded. The image is recorded, and edge detection is carried out. The image is corrected when an edge is detected.

Abstract: An image processing method suitable for a printer unit, includes an error diffusion halftoning process arranged for quantizing and diffusing each pixel of an image including a set of subtractive primary colors (C?, M?, Y?), in an image including a quantized printer image including a set of ink drops (DC, DM, DY, Dc, Dm) of respective ink channels to be printed. The method comprises the step of determining, for each pixel, an input variable value (S) representing a measure of solvent quantity that should be ejected by the printer unit for each pixel, the input variable value being computed on the basis of the value of a corresponding pixel of the image including the set of subtractive primary colors (C?, M?, Y?), and of inputting the determined input variable value (S) in the error diffusion halftoning process together with the values of the corresponding pixel. The invention further relates to the apparatus embodying the method.

Abstract: An image forming apparatus includes: a classification unit configured to classify ink colors to be superimposedly ejected in a region with a color tone change within a color image formed on a print sheet into a reference color exempted from an ejection timing correction and a correction color subjected to the ejection timing correction, for each line, based on information on comparison between minimum drop numbers acquired by a drop number acquisition unit and information on comparison between drop number distributions acquired by a distribution acquisition unit; a correction scheme acquisition unit configured to acquire a correction scheme of the ink ejection timing of the correction color in the region, for each line; and a correction unit configured to correct the ink ejection timing of the correction color in the region with the correction scheme acquired by the correction scheme acquisition unit, for each line.

Abstract: An image forming apparatus includes a controller configured to adjust ink ejection amounts from nozzles in a downstream nozzle array on a basis of a bypassing air flow degree. The bypassing air flow degree is calculated based on an ejection density of ink ejected from nozzles in an upstream nozzle array on a recording medium and indicates a generation degree of a bypassing air flow generated when a transfer air flow generated by transfer of the recording medium bypasses a self-generated air flow generated by ink ejected from the nozzles in the upstream nozzle array. The downstream nozzle array is a nozzle array located downstream in a transfer direction among a plurality of nozzle arrays. The upstream nozzle array is a nozzle array located upstream in the transfer direction among the plurality of nozzle arrays.

Abstract: Ink droplets are ejected from a plurality of dot forming elements arranged along an array direction to form dots of at least two sizes on a recording medium. If the dots formed along the array direction are classified into a plurality of groups depending on a plurality of times, the existing ratio of dots of a smaller one of the at least two sizes is higher for one of the groups of an earlier time of the times.

Abstract: A line-head control device that controls a line head includes: a calculation unit that divides image data into a plurality of areas in sub-scanning direction and calculates a printing percentage for each of the areas; an allocation unit that allocates a total correction amount, for correcting magnification of the image data in the sub-scanning direction, to the areas according to the printing percentage for each of the areas calculated by the calculation unit; and a control unit that changes an emission period of the light emitted from the line head so as to satisfy a partial correction amount that is an allocation of the total correction amount to each of the areas, exposes the image carrier to the light emitted from the line head with the changed light emission period, thereby causing a latent image to be formed on the image carrier based on the image data.

Abstract: A controller for printing a single region in which a background image is formed by the upstream background color nozzle row and the downstream background color nozzle row or in which a color image is formed by the upstream color nozzle row and the downstream color nozzle row is printed, among regions in the transporting direction, and an overlapping region in which a background image is formed by the upstream background color nozzle row and a color image is formed by the downstream color nozzle row or in which a color image is formed by the upstream color nozzle row and a background image is formed by the downstream background color nozzle row, among regions in the transporting direction, is provided. Here, the single region and the overlapping region are switched when one medium is printed.

Abstract: A printing apparatus including a head section which discharges a color ink which is cured due to irradiation of light and a clear ink which is cured due to the irradiation of light, an irradiation section which irradiates the light, and a storage section which stores a relationship between a total amount of color duty which is an amount of the color ink which is discharged per unit region and clear duty which is an amount of the clear ink which is discharged per unit region, and glossiness of an image which is printed using the color ink and the clear ink which have been discharged, wherein, according to the color duty in a certain region in the image, the clear duty in the region is determined based on the relationship so that the glossiness of the image is a predetermined value.

Abstract: A method of printing includes selectively loading a memory element during a printing operation with data that modifies a subsequent actuation of jet control elements to form or steer or form and steer print drops that print pixels on a receiver in a second regularly spaced pixel grid, the second regularly spaced pixel grid having a second spatial density of pixels extending in a direction perpendicular to a travel path of the receiver that is different when compared to a first spatial density of a first regularly spaced pixel grid, printing pixels on the receiver in the second regularly spaced pixel grid, and catching drops that are formed but not used to print pixels on the receiver in the first regularly spaced pixel grid or used to print pixels on the receiver in the second regularly spaced pixel grid.

Abstract: An inkjet printer includes an inkjet printhead having a printhead die with an array of nozzles, and a media advance system for moving recording medium along a media path toward a print region. A carriage moves the inkjet printhead back and forth across the print region, and the carriage includes a holding receptacle for the inkjet printhead. The holding receptacle includes a bottom portion having an opening into which the printhead die extends. A viewing hole is disposed in the bottom portion of the holding receptacle for providing an optical pathway between an optical sensor and a portion of the media path. A wick is configured to contact the bottom portion of the holding receptacle proximate the viewing hole for removing accumulated ink.

Abstract: Including either a platen or a flat bed, and a printer head; the printing device is configured in such a way as to print by making a combination of a reciprocating motion of the printer head and an operation of discharging ink toward a white medium. Meanwhile, the printer head includes a plurality of heads individually corresponding to each color. The printing device includes a control unit for setting a test pattern for testing each color, and pattern print areas where the test pattern is printed. The control unit makes a setting in such a way that, for the pattern print area where a test pattern is printed by discharging white ink of a nearly-identical color as a color of the white medium, the test pattern is printed with the white ink on a primer print prepared with black ink.

Abstract: In an image processing apparatus, the generating unit generates print data indicating whether a dot having one of a plurality of sizes is formed or not, by performing a halftone process on original image data. The correcting unit generates corrected print data by correcting the print data. The dividing unit divides the edge part data of the print data into a plurality of block data. The index value determining unit determines, for each block data, an index value relating to an amount of ink to be used based on the plurality of dot data included in the each block data. The changing unit changes, for each block data, the size information of at least one dot data among the plurality of dot data included in the each block data based on the index value such that the amount of ink to be used becomes reduced.

Abstract: A method of operating a printer includes reducing a first plurality of coverage parameters in a first continuous tone (contone) pixel by a predetermined amount if a combination of at least two of the coverage parameters is below a predetermined threshold and reducing a second plurality of coverage parameters in a second pixel by a smaller amount if the combination of coverage parameters in the second pixel is greater than the predetermined threshold. The method further includes generating half-tone image data from the first and second pixels and forming printed marks corresponding to the first and second pixels on an image receiving surface.

Abstract: A density variation correction method for a printing system includes printheads in at least one linehead printing a test block pattern on a print media. A density variation trace is produced for each printed test block in the test block patterns by capturing an image of each test block and averaging pixel data in a transport direction. The density variation traces associated with a known print density represented in the test block pattern are compared with a respective reference density value. A determination is made as to whether there is a difference between each density variation trace and the respective reference density value. If there is a difference, the density variation trace is adjusted to match the reference density value. The method can be repeated for all of the known print densities represented in the test block pattern and for all of the lineheads in the printing system.

Abstract: An information processing method according to an aspect of the present invention includes an attribute acquisition step of acquiring an attribute of a print medium, a reference information acquisition step of acquiring reference information corresponding to the attribute of the print medium, and an image outputting step of outputting a plurality of images having different total colorant amounts on the basis of the reference information.

Abstract: A recording apparatus includes a sensor including a light emitting element for emitting light to a recording medium, and a light receiving element for receiving the emitted light and reflected by the recording medium, configured to, via the light emitting and light receiving elements, measure a patch recorded on the recording medium by a recording head; a calibration member configured to reflect the emitted light and to be used to calibrate the sensor based on a result of optical measurement of the calibration member performed by receiving, via the light receiving element, reflected light reflected by the calibration member; and a detection unit configured to detect dirtiness of the calibration member based on the result of the optical measurement of the calibration member by the sensor and a result of optical measurement of the calibration member performed before the measurement.

Abstract: This invention provides an image forming apparatus to which a distributed control system is applied and which improves error detection accuracy in each control unit. To accomplish this, the image forming apparatus includes a master control unit which controls the overall image forming apparatus, a plurality of sub-master control units which control a plurality of functions required to implement image formation, and a plurality of slave control units which control loads required to implement the plurality of functions. Each slave control unit includes a monitoring unit which monitors the operation of the other active slave control unit and performs an error diagnosis when the slave control unit is inactive.

Abstract: The purpose is to provide a high quality halftone recording with a reduced grainy feeling without lowering the true resolving power. Provided is an apparatus for making a halftone recording by employing three or more types of color materials, each of which has at least one grade of concentration, wherein each type of the color materials having the lowest concentration provides, when recording on a recording medium having a first lightness, a recorded region having its own lightness, and wherein a difference between the first lightness and the lightness of the recorded region is not more than 35, the lightness being measured according to the definition of CIE 1976 psychological measurement lightness using a standard illuminating light D65 as a light source.